<template>
<el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
        <el-breadcrumb-item v-for="(item,index) in levelList" :key="item.path">
            <span v-if="item.redirect==='noRedirect'||index==levelList.length-1" class="no-redirect">{{ item.meta.title }}</span>
            <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
        </el-breadcrumb-item>
    </transition-group>
</el-breadcrumb>
</template>

<script>
import pathToRegexp from 'path-to-regexp'

export default {
	data() {
		return {
			levelList: null
		}
	},
	watch: {
		$route() {
			this.getBreadcrumb()
		}
	},
	created() {
		this.getBreadcrumb()
	},
	methods: {
		getBreadcrumb() {
			// only show routes with meta.title
			let matched = this.$route.matched.filter(item => item.meta && item.meta.title)
			const first = matched[0]

			if (!this.isDashboard(first)) {
				matched = [{ path: '/dashboard', meta: { title: 'Dashboard' }}].concat(matched)
			}

			this.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false)
		},
		isDashboard(route) {
			const name = route && route.name
			if (!name) {
				return false
			}
			return name.trim().toLocaleLowerCase() === 'Dashboard'.toLocaleLowerCase()
		},
		pathCompile(path) {
			// To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561
			const { params } = this.$route
			var toPath = pathToRegexp.compile(path)
			return toPath(params)
		},
		handleLink(item) {
			const { redirect, path } = item
			if (redirect) {
				this.$router.push(redirect)
				return
			}
			this.$router.push(this.pathCompile(path))
		}
	}
}
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
  display: inline-block;
  font-size: 14px;
  line-height: 50px;
  margin-left: 8px;

  .no-redirect {
    color: #97a8be;
    cursor: text;
  }
}
</style>
